1. Field of the Invention
Exemplary embodiments of the present invention relate to an apparatus capable of reducing radon in the groundwater.
2. Description of Related Art
Recently, as an interest in radon (Rn-222) increases and the number of people who want to escape from crowded and polluted cities and enjoy a rural life increases, it has become important to measure whether or not groundwater used as drinking water is contaminated by radon.
Radon is a carcinogenic substance. When radon is introduced into the human body through respiratory organs, it may cause a lung cancer. When radon is introduced into the human body through a digestive organ, it may cause a stomach cancer. When contaminated groundwater is used as drinking water, it may increase the probability that the stomach cancer occurs. Furthermore, although contaminated groundwater is not used as drinking water but used as daily life water, a secondary contamination of indoor air may increase the occurrence probability of the lung cancer.
Radon is a colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium (U-238). Radon is one of radioactive isotopes having a half-life of 3.8 days. Since radon emits alpha particles during the radioactive decay, it is known as a harmful substance for the human body. As described above, the lung cancer which is caused by inhaling radon in a gas state is most widely known as the harmfulness of radon for the human body. In accordance with the research material of the US Environment Protection Agency (EPA), radon exposure is thought to be the second major cause of lung cancer after smoking. Some countries have a radon concentration guideline. The US recommends that action should be taken starting from concentrations of 4,000 pCi/L (guideline), Finland recommends that action should be taken starting from concentrations of 8,100 pCi/L (based on drinking water), and Norway recommends that action should be taken starting from concentrations of 13,500 pCi/L (guide line).
In accordance with the information on measurement results of radon, about 10% of groundwater in Korea is thought to be contaminated by radon. Furthermore, it has been reported that a radon concentration of several thousands pCi/L is detected in groundwater of some regions. In this case, the groundwater cannot be used as drinking water.
In Korea, the actual conditions of natural radioactive substances contained in groundwater have been investigated by Ministry of Environment (MOE) since 1998. In 2008, 523 water supplies throughout the nation were investigated, which were expected to have a high natural radioactive substance content due to the geological characteristics. In accordance with the investigation result, it was checked that radon concentrations of 124 places exceeded the guideline of the US. The management of the places has been strengthened. Furthermore, MOE has operated radon reduction facilities for water supplies having a high radon concentration by way of showing an example. As a result, the effects of aeration and activated carbon and the possibility of reduction management were confirmed.